1. Field of the Invention
The present invention relates to measuring apparatus for locating a break in one or more optical fibres of an optical cable.
2. Description of the Prior Art
It is known that the very low attenuation for optical wavelengths of dielectric elements has suggested the use of these elements in light transmission systems over more or less long distances. In such systems, the conditions of use of these dielectric elements necessitate a protection or a covering in the form of a cable sheath.
One or more of the dielectric elements or optical fibres constituting the cable may break because of defective handling, or for any other reason, without the outer appearance of the cable revealing the point where such break has occurred.
What one can call "the cable to be measured" may be constituted by a single optical fibre; that is to say, an element composed of one or more dielectric materials such as glass, silica, liquid plastic material and so on, which is capable of conducting light. This optical fibre will normally form a part of a conductor constituted by one or more fibres required to transmit the same signal along parallel paths, that is a cabling element constituted by one or more conductors, or even a complete cable constituted by one or more cabling elements.